DMpay.eth — Protocol

On-chain contracts powering the DMpay.eth paid messaging protocol on Ethereum mainnet.

Frontend: app.dmpay.me · DMpay-Frontend

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Overview

DMpay.eth is a decentralised paid direct messaging protocol. Users register profiles on-chain, set a USDC price for receiving messages, and senders pay that price to open a conversation. The protocol integrates with ENS for identity (subdomains under dmpay.eth) and XMTP for end-to-end encrypted messaging.

All funds flow directly between sender and recipient — DMpay takes a 2.5% protocol fee, the remaining 97.5% goes to the recipient. No custody, no intermediaries.

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Contracts

DMPayRegistry

Manages user profiles and ENS subdomain registration.

Mainnet: 0x58d02e17bdCf0fdae2e134Da280e6084552F76f5

Key functions:

// Register a new profile with an ENS handle and USDC price
function registerProfile(string calldata handle, uint256 price) external

// Update the IPFS contenthash for your ENS subdomain
function updateIPFSHash(bytes calldata contenthash) external

// Look up a profile by handle
function getProfile(string calldata handle) external view returns (Profile memory)

// Look up a profile by wallet address
function getProfileByWallet(address wallet) external view returns (Profile memory)

On registration, the contract:

1. Creates an ENS subdomain handle.dmpay.eth via the ENS registry
2. Sets the resolver to the ENS Public Resolver
3. Sets the ETH address record on the resolver

After IPFS pinning, updateIPFSHash sets the ENS contenthash, enabling handle.dmpay.eth to resolve to a personalised IPFS profile page.

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DMPayMessaging

Handles pay-to-message payments in USDC.

Mainnet: 0x588C943Bd4f59888B2F6ECA0b2BfB123B57b0a10

Key functions:

// Open a paid conversation (sender pays recipient's price in USDC)
// Requires prior USDC approval for this contract
function openConversation(address recipient) external

// Check if a conversation between sender and recipient is open
function isConversationOpen(address sender, address recipient) external view returns (bool)

Payment flow:

• Sender calls openConversation(recipient) after approving USDC
• Contract reads recipient's price from DMPayRegistry
• 2.5% fee sent to protocol treasury
• 97.5% sent directly to recipient
• Conversation flagged as open on-chain

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Deployments

Mainnet

Contract	Address
DMPayRegistry	0x58d02e17bdCf0fdae2e134Da280e6084552F76f5
DMPayMessaging	0x588C943Bd4f59888B2F6ECA0b2BfB123B57b0a10
ENS: dmpay.eth node	0x2059bd34c28c7a6645dd35be7e5dcc4b3e4999849bbe8b2c8b838f2d4cfc3ec8
ENS Public Resolver	0xF29100983E058B709F3D539b0c765937B804AC15
USDC	0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48

Sepolia (Testnet)

Contract	Address
DMPayRegistry	(deploy via Ignition — see below)
DMPayMessaging	(deploy via Ignition — see below)
MockUSDC	Deploy MockUSDC first for testing

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Getting Started

Prerequisites

• Node.js 20+
• An Ethereum RPC URL (Alchemy or Infura recommended)
• A funded deployer wallet private key

Install

git clone https://github.com/RWA-ID/DMpay-Protocol.git
cd DMpay-Protocol/contracts
npm install

Environment Variables

Create a .env file inside contracts/:

MAINNET_RPC_URL=https://eth-mainnet.g.alchemy.com/v2/your_key
SEPOLIA_RPC_URL=https://eth-sepolia.g.alchemy.com/v2/your_key
PRIVATE_KEY=your_deployer_private_key
ETHERSCAN_API_KEY=your_etherscan_key

Compile

npx hardhat compile

Test

npx hardhat test

Deploy to Sepolia

npx hardhat ignition deploy ignition/modules/DMPay.ts --network sepolia

Deploy to Mainnet

npx hardhat ignition deploy ignition/modules/DMPayMainnet.ts --network mainnet

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Project Structure

contracts/
├── contracts/
│   ├── DMPayRegistry.sol        # Profile registry + ENS subdomain manager
│   └── DMPayMessaging.sol       # Pay-to-message USDC payment handler
├── ignition/
│   └── modules/
│       ├── DMPay.ts             # Sepolia deployment module
│       └── DMPayMainnet.ts      # Mainnet deployment module
├── scripts/
│   └── send-op-tx.ts            # Utility for sending ops transactions
├── setContenthash.mjs           # Script to manually set ENS contenthash (Sepolia)
├── setContenthashMainnet.mjs    # Script to manually set ENS contenthash (Mainnet)
├── setSubdomainContent.mjs      # Script to set subdomain content records
├── hardhat.config.ts            # Hardhat configuration
└── test/
    └── Counter.ts               # Contract tests

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Architecture

Sender                 DMPayMessaging            DMPayRegistry
  │                         │                        │
  │── openConversation ────>│                        │
  │                         │── getProfile ─────────>│
  │                         │<── price ─────────────-│
  │                         │                        │
  │                         │── transferFrom(sender, recipient, 97.5%)
  │                         │── transferFrom(sender, treasury, 2.5%)
  │                         │── mark conversation open
  │<── success ────────────-│                        │

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ENS Integration

Each registered user gets a subdomain under dmpay.eth:

• Registry node: keccak256(dmpay.eth namehash + keccak256(handle))
• Resolver: ENS Public Resolver (0xF29100983E058B709F3D539b0c765937B804AC15)
• Address record: Set to user's wallet address
• Contenthash: Set to IPFS CIDv1 after profile page is pinned

The dmpay.eth parent domain is managed by the DMpay deployer wallet. DMPayRegistry is approved via setApprovalForAll on the ENS registry, allowing it to create subdomains on behalf of the owner.

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Security

• No admin keys for individual user profiles — once registered, only the wallet owner can update their IPFS hash
• Protocol fee rate is set at deployment and enforced by the immutable smart contract
• All USDC flows are atomic — payment and conversation-open happen in a single transaction
• No contract upgradeability — what is deployed is what runs

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